Patent GB-806443-A (GB)
Title: Improvements in and relating to fuel injection nozzles
IPC: F02M61/08
Filed: 1955-07-22
Abstract: 806,443. Spray burners. PARKER-HANNIFIN CORPORATION, [formerly PARKER APPLIANCE CO.]. July 22, 1955 [Aug. 23, 1954], No. 21321/55. Class 75(1) [Also in Group XXVII] A fuel injection nozzle comprises a swirl chamber immediately upstream of an exit orifice, a normally open passage and a plurality of normally closed passages each leading from the intake end of the nozzle to the swirl chamber and each including a helical terminal portion adapted to deliver a swirling flow to the chamber, a regulating valve member 14 being adapted to open sequentially the normally closed passages in response to increase in fuel intake pressure. The nozzle has an exit orifice 12 and may comprise an exit valve member 27 normally closing such orifice and means for connecting the regulating valve member and exit valve member. When the fuel pressure reaches the necessary value the valve members 14, 27 are shifted to the right and the orifice 12 is opened. Fuel then passes through ports 18, 19, 20, which are always open, to channels 15, 16, 17 and helical swirl grooves 24. It passes through the exit orifice in the form of a spray cone. When the pressure is effective to shift the valve member 14 to uncover port 42 additional fuel flow is admitted to the remaining helical grooves 24 by way of longitudinal channels 36-41. As the rate of fuel flow is increased the valve member is shifted to the right bringing the bevelled shoulder of the same past the edge of the annular inlet port 64. Fuel enters such port to an increasing extent as the valve opens and passes therefrom through channels 55-63 and swirl slots 66 to the orifice 12. The bore 13 may be contoured in the regions adjacent the inlet ports instead of bevelling the valve member 14 as shown. If desired even more precise control may be obtained by providing additional channels and ports sequentially opened as valve member 14 is operated. Port 42 is very narrow where it enters the bore 13. Preferably it is only a few thousandths of an inch wide. Ports 42 and 64 may desirably be spaced only a few thousandths of an inch apart the space therebetween preferably not exceeding eight thousandths of an inch for a common size of jet engine nozzle and the width of the opening of port 42 may likewise desirably not exceed eight thousandths of an inch in such case. Another longitudinally extending channel 67 is provided and communicating through a very restricted orifice 69 with an annular filtered fuel passage 8. Radial passages 70, 71 and 72 lead to the bore 13 and to the bore of the end member 25. See also Specification 763,975. Compression spring 34 may desirably be formed from a length of tubing slotted by two helical slots. The interior of the valve 14 is vented through the passage 31. In Fig. 13, the exit orifice valve member is dispensed with. As shown, the spring 34 is compressed so that fuel is escaping through both ports 42 and 64. Shim 74 will be selected so that under normal conditions with minimum intake pressure the valve member 14 will close both such ports but will not close port 18. There will consequently normally be a very slight escape of fuel through the exit orifice 12 when the intake end pressure is very low. If desired member 75 may be formed without the neck 76. The Specification refers to throttling an engine up and down by regulating the fuel flow to a definite number of nozzles rather than providing means for shutting off and turning on additional nozzles. The nozzles are suitable for turbo-jet, prop-jet and ramjet engines. Specification 741,838 and 747,582 also are referred to.